Tavi Gevinson is the pint-sized style guru who, at the age of 11, created the wildly popular blog for teenage girls, "Style Rookie."

By age 14, she was hanging out with Chanel's Karl Lagerfield and sitting front row next to Vogue's editor-in-chief Anne Wintour at New York City's Fashion Week.

Gevinson has graced magazine covers, has been the muse for the edgy Rodarte sisters' clothing line for Target, and now, at the ripe old age of 16, she has established herself as a sort of oracle for the inner workings of the teenage psyche. She even gave a talk at a TEDx conference on it.

But at 7:30 a.m. on a Friday morning, she is just your average high school junior getting ready for school.

"I've gone to school with jeans and a sweatshirt on," she said. "I have weirder outfits that I want to wear but I save them for outside of school."

But Gevinson does lead a double life: She is a normal teenager by day and a burgeoning media mogul by night. When she launched "Rookie," her online magazine, it received 1 million views in its first week.

"It's weird to sit in school and be, like, I have a deadline, I have all of those emails I have to get back to, and only one person will see my homework, my teacher, but all of these other people will see my article," she said. "That's a weird balance to figure out."

It all started in her slightly cluttered bedroom in suburban Oak Park, Ill., which is filled with vintage accessories and pop culture paraphernalia. Gevinson gets her Bohemian looks from her mother, who is a Swedish-born artist. Her father is a retired high-school English school teacher.

Five years ago, the then-11-year-old Gevinson borrowed her dad's laptop and started posting photos of herself in eclectic, avant garde outfits in a signature funny, precocious voice. Those posts became "Style Rookie."

"I was in sixth grade," she said. "I just thought it would be fun to chronicle my interest in fashion as it was developing and changing."

Tens of thousands of clicks later, Gevinson was the toast of Fashion Week, Teen Vogue dubbed her "the luckiest 13-year-old on the planet," but she also drew snarky criticism by showing up to shows wearing eccentric pieces, like an enormous Stephen Jones bow that she wore to a Christian Dior fashion show.

"If you are a public person at all and you are aware of criticisms people have about you, you are sort of constantly worried about them being true," she said.

The latest phase of her career is expanding her horizons to talking about things beyond fashion, to arts and crafts, and essays on everything from Joni Mitchell to midnight snacking, as well as more serious topics like broken hearts, eating disorders and sexuality.

"We don't write about sex or anything for shock value," Gevinson said. "It's just because I think about the conversations I have with my friends or that I overhear and I think about what people feel like they are missing."

So what makes "Style Rookie" different from, say, "Seventeen" magazine? Gevinson said her magazine doesn't cater to what advertisers want.

"I do think there's just a general tone that can feel sort of condescending in a lot of writing or movies or TV shows that are made for teenagers, and I think a lot of it does come from wanting to teach, and that comes from like a really honest place," she said. "But it's not always gone about honestly, and so it just feels like a PSA that you would see in school and no one takes them seriously."

"Rookie" strives to be an authentic forum for the issues facing teenagers and is published on a schedule that is tailored to a high-schooler.

"We post after school, around dinner time and around bed time," Gevinson said. "When we were starting this, my dad was like, 'How are you going to do this? You are in school during the day,' and I was like, 'Well, so is everybody else so I'll just post when we all get home.'"

The site has such cachet it has attracted high-profile contributors like HBO "Girls" creator Lena Dunham, comedian Sarah Silverman. And, for the girl who loves the '60s "Mad Man" aesthetic, even the AMC show's star, Jon Hamm.

While wearing a 5 o'clock shadow and a St. Louis Cardinals t-shirt, the "Mad Men" actor gave "Rookie" readers hysterical, but honest, advice about what boys are thinking in a Q&A session. Hamm answered one question from a 16-year-old girl who asked what she should do about being ready to "do stuff" with her boyfriend of three weeks when he didn't want to.

"I am going to have to know what this [air quotes] stuff is," Hamm said. "If it is making out, he should want to do that, it's super fun. If it's having sex, that has other things to deal with. Then he's probably right to say slow your roll."

"His thing was that he is sort of very uncomfortable answering these questions about sex from teenage girls and that worked out great," Gevinson said.

But the uber-literate, style-conscious teen does admit to having weak spots. For one, she said she is a "horrible" driver who failed her driving test. And yet, she has employees who work for her, some of whom are in their 40s.

"They are all there because they take our audience seriously," Gevinson said. "At the risk of sounding cheesy, there is a lot of love that goes into working on 'Rookie' and it absolutely would not work if the people working on it didn't respect the intelligence of teenagers."

The truth is that teenagers are complicated. They are a bundle of contradictions, bravado laced with insecurity, with moments of joy and angst.

"Being a teenager is just, kind of, inevitably horrible," Gevinson said. "But I think a lot of the sadness or angst or any of the problems teenagers deal with are often sort of brushed aside because they are teenagers so people think, 'It's just a phase,' or, 'He or she is just being a teenager.'"

It's that kind of raw honesty that makes Gevinson an inspiration to young girls.

Some parents have asked me, 'This book has a lot of serious stuff in it; is it OK to give my daughter?'" she said. "And I feel like those are already things that like 12-, 13-year-olds know about and are talking about with their friends. And here is at least one person's honest account of it."